Simultaneous production of ²⁸Mg and ⁴⁷Ca by high-energy heavy-ion irradiation for applications in biology

With the aim of preparing carrier-free ²⁸Mg and ⁴⁷Ca simultaneously, Ti, V and Fe targets were examined by irradiating with high-energy ions of ¹²C, ¹⁴N and ¹⁶O accelerated by the RIKEN Ring Cyclotron. Among the targets, V gave the highest cross section for the formation of both ²⁸Mg and ⁴⁷Ca irrespective of the kind of beams. The cross section for the formation of ²⁸Mg by the reactions of Ti, V and Fe targets with ion beams increased in the order of ¹²C<¹⁶O<¹⁴N. On the other hand, the three beams exhibited almost the same cross sections for the formation of ⁴⁷Ca by the reaction of a given target. Titanium and V were selected as prospective targets and ¹⁴N as a suitable beam for the production of ²⁸Mg and ⁴⁷Ca. Chemical separation procedures of the radiotracers in carrier- and salt-free states have been established by using cation exchange resins. The recovery yields of ²⁸Mg and ⁴⁷Ca from Ti target were 70 and 90%, respectively, and the decontamination factor was less than 10^-5. The recovery yields of ²⁸Mg and ⁴⁷Ca from V target were 80% and the decontamination factor was less than 10^-7.